Plastic case for milk bottles



April 14, 1970 'r. w. BARNES 3,506,154

I PLASTIC'CASE FOR MILK BOTTLES Filed Juiy a. 1968 3 Sheets-Sheet 1 Apri 14, 1 970 'w, BARNES v 3,506,154

' PLASTIC CASE FOR MILK BOTTLES Filed July 8. 1968 v 3 Sheets-Sheet 2 III 11/4 I I n April 14, 1970 T. w. BARNES 3,506,154

PLASTIC CASE FOR MILK BOTTLES Filed July 8, 1968 3 Sheets-Sheet :s

v I "III 73 Wagfl Zia/ 7265 lab/4 W ZWZQJZ XLMaMMAZwa United States Patent 3,506,154 PLASTIC CASE FOR MILK BOTTLES Tracy W. Barnes, Peoria, Ill., assignor to Laidlaw Corporation, Peoria, 111., a corporation of Illinois Filed July 8, 1968, Ser. No. 743,117 Int. Cl. 865d 7/42 U.S. Cl. 220-83 6 Claims ABSTRACT OF THE DISCLOSURE A four sided milk bottle case is molded from a plastic material to form an integral double wall container with an air space between the walls. The air space may be filled with a cellular plastic material. Openings provided for handles in the sides of the case and in the bottom of the case impart rigidity to the structure. The handle openings may include a hard plastic or a metal insert.

BACKGROUND OF THE INVENTION This invention relates to a case for containers such as milk bottles and the like and, more particularly, to a plastic case for milk bottles or cartons which is integrally molded from plastic material.

Cases for carrying bottles or cartons of beverages such as milk preferably have a number of characteristics. 'For example, such cases are necessarily lightweight so that they may be easily handled. In addition such cases also have insulating properties to keep the beverages such as milk cool during transportation. Finally is their capability to be stacked one on top of the other either during use or when not in use.

Innumerable patents have been granted on various case constructions attempting to satisfy these and other criteria which may appear necessary for a packaging situation. The present invention of an improved carrying case for containers such as milk bottles or the like provides many features and advantages not heretofore realized.

SUMMARY OF THE INVENTION In a principal aspect the present invention of a case for containers such as milk bottles or the like comprises a case with at least three sides and a bottom each having molded double walls of a rigid plastic material. The double walls forming the sides and bottom are integrally connected with each other and the case includes numerous openings through the double walls defined by integrally molded connections between the double walls.

It is thus an object of the present invention to provide an improved case for containers such as milk bottles or the like.

It is a further object of the present invention to provide a case having inner and outer walls with a hollow region defined between the walls.

One further object of the present invention is to provide a case for containers which is lightweight and easy to handle.

Still another object of the present invention is to provide a case for containers which is economical to manufacture and easy to store.

One further object of the present invention is to provide a case for containers which insulate the containers Within the case.

These and other objects, advantages and features of the present invention will be set forth in greater detail in the description which follows.

BRIEF DESCRIPTION OF THE DRAWINGS In the detailed description which follows reference will be made to the drawings comprised of the following figures.

FIG. 1 is a perspective view of a four-sided milk bottle case of the invention;

FIG. 2 is a side view of a side of the case shown in FIG. 1;

FIG. 3 is a top plan view of a corner of the case shown in FIG. 2 taken substantially along the line 33 of FIG. 2;

FIG. 4 is a bottom view of the case taken substantially along the line 44 of FIG. 2;

FIG. 5 is a partial cross sectional side view of the walls of the case taken along the line 55 of FIG. 2;

FIG. 6 is a partial cross sectional view of a side and the bottom of the case taken substantially along the line 66 of FIG. 2 or FIG. 4;

FIG. 7 is an enlarged partial cross sectional view of a handle opening through a side of the case;

FIG. 8 is a plan view of the handle opening through a side of the case including a plastic insert;

FIG. 9 is a cross sectional view of the handle opening of FIG. 8 taken substantially along the line 9-9;

FIG. 10 is a cross sectional view of the handle opening of FIG. 8 taken substantially along the line 1010;

FIG. 11 is a plan view of analternative handle construction for the case;

FIG. 12 is a cross sectional view of the handle shown in FIG. 11 taken on the line 1212;

FIG. 13 is a cross sectional view of the handle of FIG. 11 taken substantially along the line 1313;

FIG. 14 is a plan view of a third alternative handle construction for the milk bottle case;

FIG. 15 is a cross sectional view of the embodiment shown in FIG. 14 taken substantially along the line 1515;

FIG. 16 is a cross sectional view of the handle construction of FIG. 14 taken substantially along the line 1616; and

FIG. 17 is a cross sectional view of the handle construction of FIG. 14 taken substantially along the line 17-17.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to FIG. 1 there is shown in a perspective view the preferred embodiment of a case for containers of the present invention. The case shown in FIG. 1 is adapted especially for carrying sixteen one quart or nine one-half gallon milk bottles or cartons. However, any other desirable case size or shape is within the scope of the invention. The case includes four connected sides 2124 and a bottom 25. The bottom 25 is continuously or intogrally molded with the sides 21-24 as illustrated in FIG. 1 and described below. The sides 21-24 terminate in a rounded top ridge 26.

Each of the sides 2124 has substantially the same construction and thus a description of side 21 will serve as a description for the remaining sides 22, 23 and 24. As illustrated in FIGS. 3, 5, 6 and 7, the side 21 is formed from a rigid plastic material inner wall 28 and a rigid plastic material outer wall 30. As can be appreciated by reference to the drawings the inner and outer walls 28 and 30 are separated from each other by a substantially uniform distance to define an enclosed hollow region between them. Preferably a high density polyethylene material is used for constructing the case of the invention including the inner and outer walls 28 and 30. Typically such a high density polyethylene will have a density of 0.953 grams per cubic centimeter with a 6 second melt index. Thus, the total weight of the sixteen quart case being described is approximately four pounds.

The side 21 also includes a handle grip opening 32 and a pair of spaced openings or passages 34 and 36 through the side 21. The handle grip opening 32 and the passages 34 and 36 are defined by the same rigid plastic material defining the inner and outer walls 28 and 30. The inner and outer walls 28 and 30 are thus connected by a smooth continuous extensions of the material forming the walls. The connecting material between the inner and outer walls 28 and 30 which defines the passages 34 and 36 and the handle grip opening 32 serves to add structural rigidity to the side 21. Thus, while a single handle grip opening 32 and two passages 34 and 36 are shown in the figures, additional openings or passages may be defined through the side 21 for additional structural rigidity. On the other hand, additional openings will reduce the insulating effect created by the hollow enclosed region between the walls. The embodiment described presents a compromise between these two factors of structural rigidity and insulating ability.

Each of the sides 2124 is of the construction described. As illustrated in FIG. 3 the inner and outer walls 28 and 30 of each of the sides 21-24 are continuous so that the hollow enclosed region in the side remains uninterrupted completely around the circumference of the case. Moreover, the inner wall 28 includes a bulge 38 along the junction between sides 21 and 22, extending toward the outer wall 30. Similarly the junction between the other adjacent pairs of sides includes a bulge such as the bulge 38. Thus when a square edged milk carton or the like is positioned within the case as illustrated in FIG. 3, the corner of the carton 40 will fit into the bulge 38 so that the side wall and bottom of the carton abuts the corresponding walls of the case. FIG. illustrates the corner construction at the junction between adjacent sides 21 and 24.

As illustrated in FIG. 6 the bottom 75 also inclndes an inner wall 42 and an outer wall 44. The inner and outer walls 42 and 44 are. smoothly and continuously or integrally molded to define a plurality of passageways or openings through the bottom 25 such as at 46 and 48 in FIG. 6. In the embodiment shown by the drawings the number of openings through the bottom is sixteen, as illustrated in FIG. 4. The openings may be arranged in a pattern so that the openings will coincide substantially with the center bottom wall of one quart cartons or milk bottles placed in the case. Obviously the arrangement and number of openings may be varied depending upon the desires of the user and structural considerations as described previously.

Very importantly the inner wall 28 and outer wall 30 forming the sides 21-24, are integral with the inner wall 42 and outer wall 44 respectively of the bottom 25. This is illustrated in FIGS. 4 and 6. Thus, the case of the invention consists of a unitary molded wall of plastic material forming the inside, outside and connecting portions of the entire case. The single molded wall is integrally formed into a double walled case with the double wall enclosing a hollow air space that serves to insulate the contents of the case. The double wall construction rigidly supports the case contents as well as numerous stacked cases as described below.

A circumferential or peripheral ridge 50 defined in bottom wall 44 extends around the bottom 25 of the outside of the case and is adapted to coact with the circumferential top ridge 26 so that cases may be stacked one upon the other. Also, as illustrated in FIGS. 4 and 6, the bottom 25 includes a plurality of intersecting ridges defined by the outer wall 44. Crisscrossing ridges as at 52, 54, 56, 58, 60 and 62 are defined in the outer wall 44 so that the openings through the bottom 25, described above, are all separated from one another. These ridges provide structural rigidity to the case and to the bottom which supports the weight of cartons positioned within the case.

The hollow dead air space between the inner walls 28,

2 and outer walls 20, 44 respectively provides insulating characteristics which keep the milk or liquid in the containers within the case cool. Alternatively an expanded resin foam, e.g. isocyanate material, may be included in 4 the hollow region between the inner and outer walls to further enhance the insulating characteristics of the case. As a typical example, a resin foam 45 is provided between the walls 42 and 44 in FIG. 6 for a portion of the case illustrated in FIG. 6.

One way to make the case of the present invention by the rotational molding process. This process is well known by those skilled in the art of plastic molding and general description of this process may be found in the Modern Plastics Encyclopedia, 1967.

Another method of fabricating the case of the present invention is by means of injection molding of an expanded or foamed resin, e.g. polyolefin directly into a mold. That part of the cellular material directly touching the mold walls will be immediately chilled and form a high density non-porous skin; whereas the expanded material in the region between the mold walls will remain a low density material. In this manner the hollow space between the inner and outer walls forming the bottom and sides of the case will automatically include a cellular material, formed in a single injection molding operation.

Referring now to FIGS. 8 through 17 there are disclosed three alternative embodiments of handle constructions for the case of the present invention. In FIGS. 810 a first alternative embodiment of the handle construction is illustrated. There a high density, high melt index polyethylene plastic material is molded separately from the case in the form of a handle 64 which has a circumferential ring portion 66 and a center brace 68. The handle 64 is placed in the case mold and low-melt polyethylene is molded around the wedge shaped ridge 70 of ring 66 as the case is formed. The handle is not deformed because of the difference in softening points of the resins used.

In FIGS. 11-13 there is shown an inner and an outer galvanized steel plate 74 and 76 respectively which are adapted to fit against inner and outer walls 28 and 30 respectively through a handle grip opening. The plates 74 and 76 include outside flanges and 77 respectively which are molded in the inner and outer walls 28 and 30 respectively to facilitate holding the plates 74 and 76 in an immovable position. The plates 74 and 76 are either tack welded or resistance welded together and then molded into the case during the molding operation.

FIGS. 14-17 show a third alternative embodiment of a handle grip opening reenforcement. Here a single galvanized sheet or plate 78 of steel is molded in the inner wall 28 of the side of the case so that a circumferential depression 79 prevents the plate 78 from slipping. The plate 78 is also maintained in position by means of tabs 81-84, one tab being defined at each of the four corners of the plate 78. For example, tab 81 is made, as shown in FIG. 17, by bending the corner of the plate 78 down and outwardly. Then the tab 81 is molded the case during the molding operation so that a tab receiving insert 86 is defined in the inner wall 28 of the side. In. this manner the plate 78 is rigidly held against the inner wall 28 of the case and serves to strengthen the handle grip opening.

What is claimed is:

1. A unitary, integrally molded plastic case for containers such as milk cartons and the like comprising, in combination:

four pairs of substantially parallel, spaced side walls and a pair of spaced bottom walls, each pair of side walls comprising an inner wall and an outer wall having a top edge, side edges and a bottom edge, each pair of side walls being continuously joined together at said top edge to form a top ridge, adjacent inner and outer side Walls respectively joined together continuously at said side edges and with said inner and outer bottom walls respectively to provide an enclosure the interior of which is defined by said inner side walls and said inner bottom wall and the exterior of which is defined by said outer side walls and said outer bottom Wall, said pairs of spaced walls also including integrally formed continuous connections therebetween defining apertures through said walls; said outer bottom wall including an outwardly extending bottom ridge, said bottom ridge being dimensionally less than said top ridge such that said top ridge extends around a bottom ridge of the next successive case in a stack of cases.

2. The case of claim 1 including bulges in said inner side walls at the junction of each pair of said side walls, each of said bulges extending toward said outer side walls to provide for receipt of angular edges of containers in said case along said junction.

3. The case of claim 1 wherein said apertures include at least one handle grip opening positioned in one of the pair of side walls of said case.

4. The case of claim 3 wherein said handle opening includes a plastic insert.

5. The case of claim 3 wherein said handle opening includes a metal insert.

6. The case of claim 1 including a cellular plastic material in between said spaced walls,

said cellular plastic material having a lower density than said rigid plastic material and acting as insulating means.

References Cited UNITED STATES PATENTS Simon et a].

Cohen 52-619 X Miskella 52-619 Stevenson 220-21 Garcia 220-21 Cloyd 220-21 Beesley et a1.

Blessing 220-15 Christenson.

Smalley.

Australia.

U.S. Cl. X.R. 

